Describe in detail what happened including the concern or potential issue, the environment (weather, terrain, fire behavior, etc), and the resulting health issue.

Last day on the shift private aircraft were doing practice landings and takeoffs at the Deadwood Airstrip. During this time, the two line safety officers were acting as road guards to keep vehicles from passing on the uphill side of the airstrip. A pickup working for the fire passed one of the safety officers and then proceeded to drive down the runway thus disregarding the signs and the road guards. The plane did a landing and turned around at the uphill side of the runway to take off. At this time the vehicle pulled out at the bottom of the runway but waited off to the side while the aircraft took off. When the aircraft cleared the vehicle drove back up the runway to enter road 555 but was stopped by both safety officers and briefed, then released.

Immediate Action Taken

Reporting Individual : please describe actions you took to correct or mitigate the unsafe/unhealthful event.

Lead safety was briefed and in the future when there are open back country airstrips all personnel are briefed with this emphasis.